On October 12, 2020, the Exchange experienced an issue with a subset of internal monitors. The trading platform was not impacted. The issue manifested itself in the inability to fully view the trading data in a subset of the operational monitoring dashboards. Out of an abundance of caution for the greater marketplace, MEMX chose to halt pre-market trading at 09:15 ET and delay the opening of the Exchange. The system was normalized and full monitoring capabilities were restored and validated prior to the resumption of trading at 11:33 ET.